Advances in radiopharmaceutical have dramatically escalated the use of intraoperative gamma probes in surgery. Such probes provide benefits of increased tissue specificity obtained for biopsy, minimally accessed incisions, and the reduction of inpatient hospital utilization with an improved patient recovery. At present most of the probes on the market are non-imaging gamma probes that suffer from the lack of ancillary information of the surveyed area, such as clear delineation of malignant tissue. Also, the highly penetrating gamma radiation arising from other parts of the body increases the background and limits the practical use of these probes. We are addressing these limitations by designing a new-generation intraoperative probe intended to rapidly image the tumor bed with short-range beta rays. The probe is based on a combination of two innovative technologies, namely a high resolution, high efficiency scintillator coupled to a high sensitivity, low noise readout sensor. The proposed device will allow real time imaging of the surveyed area for rapid and accurate delineation of lesions. The Phase II research will be focused on developing a fully functional prototype and demonstrating its efficacy by performing detailed animal studies. This new imaging technology has enormous potential in both medical and non-medical applications. The estimated market size for probes and other technologies being developed under this program is well over one hundred million dollars. A significant fraction of this market represents areas where the involved technologies will have a major impact. [unreadable] [unreadable]